1. Protective covers of power shafts are very important elements since they protect the hinges of equal angular speeds (HEAS) from the hit on them of dirt, water and other foreign objects causing damages. External pollution of protective covers oil and lubricants can lead to premature failure of material of covers therefore it is recommended to wash periodically covers with water with soap.

2. Examine covers on existence of gaps and cracks, and also the weakened collars. In case of detection of signs of cracks or leak of lubricant the cover has to be replaced.

3. At the same time check the general condition of hinges of equal angular speeds, holding a shaft and at the same time trying to turn a wheel. Repeat attempt, holding the internal hinge of equal angular speeds and turning a shaft. Any noticeable side play indicates wear of the hinge, wear in grooves of a shaft or an otvorachivaniye of a lock nut of a shaft.